/***********************************************************************
* Name: get_ant_msg
*
* Description: wait and recieve a message from the nRF24AP2
*
* Author(s): Charles Wolf
*
* @param:
* int max_wait -> timeout in 1mSec increments
* UCHAR *MSG -> pointer to the message array
* @return:
* int -> 0 = message timeout
* 1 = message recieved
* Comments:
* ANT Message Structure
* SYNC (0xA4) 1 Byte
* length 1 Byte
* message ID 1 Byte
* Data length
* CheckSum 1 Byte
*
* ********************************************************************/
int get_ant_msg(int max_wait, UCHAR *MSG)
{
int count = 0;
int i = 0;
int outcome = 0;
int length = 0;
int checksum = 0;
softuart_turn_rx_on();
softuart_flush_input_buffer();
while((count < max_wait) && (outcome != 1))
{
//wait for data
while((softuart_kbhit() < 1) && (count < max_wait))
{
_delay_us(100); // 1bit = 208.333uSec
count++;
}
if ( softuart_kbhit() > 0 )
{
outcome = 2; //no sync
//check for sync
MSG[0] = softuart_getchar();
//softuart_getchar() is a possible place to get stuck waiting
if(MSG[0] == MESG_TX_SYNC)
{
MSG[1] = softuart_getchar(); //length
length = MSG[1]+2;
if(length > 17) length = 17; //protect length
for (i = 0; i < length; i++)
{
MSG[i+2] = softuart_getchar();
}
checksum = checkSum(&MSG[0], length+3);
if (checksum != MSG[length+4])
{
outcome = 3; //bad checksum
}
else
{
outcome = 1; //message recieved
}
}
}
}
softuart_turn_rx_off();
return outcome;
}
/** Flushes the serial port Buffer
*
* This function reads one character from the serial port
* if available.
*
*/
void clixxIOSerial::flush(void)
{
// flush the buffer
softuart_flush_input_buffer();
}
void motor_reqPos(uint8_t motor){
softuart_flush_input_buffer(motor);
softuart_puts(motor, POSITION);
}
